From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nayna Subject: Re: [PATCH v7 2/2] tpm: add securityfs support for TPM 2.0 firmware event log Date: Wed, 4 Jan 2017 14:08:06 +0530 Message-ID: <586CB46E.8050207@linux.vnet.ibm.com> References: <1481434533-3453-1-git-send-email-nayna@linux.vnet.ibm.com> <1481434533-3453-3-git-send-email-nayna@linux.vnet.ibm.com> <20170102221148.gy3mlubrgs4gm6ey@intel.com> <586B5526.9090703@linux.vnet.ibm.com> <20170103133309.lt5k4c37rjq5vcbq@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20170103133309.lt5k4c37rjq5vcbq-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: tpmdd-devel-bounces-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org To: Jarkko Sakkinen Cc: linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-security-module-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, tpmdd-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: tpmdd-devel@lists.sourceforge.net On 01/03/2017 07:03 PM, Jarkko Sakkinen wrote: > On Tue, Jan 03, 2017 at 01:09:18PM +0530, Nayna wrote: >> >> >> On 01/03/2017 03:42 AM, Jarkko Sakkinen wrote: >>> On Sun, Dec 11, 2016 at 12:35:33AM -0500, Nayna Jain wrote: >>>> Unlike the device driver support for TPM 1.2, the TPM 2.0 does >>>> not support the securityfs pseudo files for displaying the >>>> firmware event log. >>>> >>>> This patch enables support for providing the TPM 2.0 event log in >>>> binary form. TPM 2.0 event log supports a crypto agile format that >>>> records multiple digests, which is different from TPM 1.2. This >>>> patch enables the tpm_bios_log_setup for TPM 2.0 and adds the >>>> event log parser which understand the TPM 2.0 crypto agile format. >>>> >>>> Signed-off-by: Nayna Jain >>> >>> There is something fundamentally wrong in this commit. >>> >>> You must not allow this feature unless CONFIG_OF is set. It is the only >>> interface where the supply path of the event log is well defined on >>> platforms that include a TPM 2.0 chip. >> >> As per current implementation, if ACPI with TPM 2.0 doesn't support event >> log, tpm_read_log_acpi() is expected to return rc and tpm_bios_log_setup >> will not create securityfs. This is inline with our design for TPM 1.2 event >> log. > > At minimum you must have a check for TPM_CHIP_FLAG_TPM2 in the beginning > of tpm_read_log_acpi. It is wrong to even try to open TCPA in this case. Sure, will add this check and return -ENODEV if check passes. Thanks & Regards, - Nayna > > /Jarkko > ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, SlashDot.org! http://sdm.link/slashdot